Sultan,
Thanks for the lesson in Math 1.01, but that doesn't explain it.
Look at the second set of figures in brackets - those are the original PMO/Bell-Boeing estimates. So by your logic, unless the V-22 is flying significantly faster than originally predicted or carrying a significantly higher payload, there's something else going on here.
I still suspect part of the answer is in the way the Osprey is being utilized in-theater. It could be something as simple as average mission duration being lower than originally projected, due to a reliance on flights from 'friendly' airbases in the 'Stans (as opposed to an original Cold War scenario of operations from LHDs based in the Sea of Japan).
I/C